Secretary of State Brian Kemp says voters can submit an application online or mail hard-copy applications. Mail-in applications must be postmarked on or before Monday’s date to be processed in time.

More than a dozen candidates are competing in the April 18 contest to fill the seat representing many of Atlanta’s northern suburbs and formerly held by Tom Price. Price, a Republican, is now secretary of the Department of Health and Human Services.

Georgia requires a so-called “jungle primary” to fill congressional vacancies. The top two vote-getters, regardless of party, move to a June 20 runoff.

Early in-person voting will begin on March 27. Polls also will be open Saturday April 8.